Electronic cigarettes are a kind of simulating cigarettes which heat and atomize materials having flavors through heating wire to generate smoke for user's suction, the electronic cigarettes are usually placed within the electronic cigarette casing, the electronic cigarettes generally comprises detachable sucking rod and power rod, and the electronic cigarette casings commonly use a rechargeable battery to store energy and charge the electronic cigarettes. During charging the power rod is inserted into the charging socket inside of the electronic cigarette casing in order to be connected with and charged by the rechargeable battery in the electronic cigarette casing.
However, the electronic cigarette casing with rechargeable battery has the defects of less charging and discharging times, being unsafe (ease to fire and explode), long charging time, small charging current and so on.